Negative dyes and coloration process using them

ABSTRACT

The present invention relates to a water-soluble reactive dye of the formula N(Z) 3 , wherein each Z independently has the formula (III): ##STR1## wherein m, Q, Y and D are defined in the claims. The present invention also relates to a process for coloring a substrate that includes applying to the substrate the water-soluble reactive dye of the above formula at a pH above 7.

This application is a Continuation of application Ser. No. 09/068,550filed on Jun. 8, 1998, now U.S. Pat. No. 5,968,208 which is a 371 ofPCT/GB96/02633 filed Oct. 30, 1996 allowed.

This invention relates to reactive dyes, their preparation and use.

The use of a reactive dyes for colouring cellulosic substrates has beenknown for many years. Environmental legislation has lead to strictercontrols on dyehouse effluent, e.g. waters containing salt and unfixeddye, and effluent disposal now represents a major cost to dyehouses. Toreduce such costs there is a need for reactive dyes which can be used ina way which produces less effluent, for example dyes having highfixation efficiency and/or requiring less salt during the fixationprocess. Reactive dyes having these properties and the ability tobuild-up to high depths of shade would be particularly valuable.

According to the present invention there is provided a process for thecoloration of a substrate comprising applying thereto at a pH above 7 awater-soluble reactive dye comprising at least three chromophoric groupslinked to a polyamine.

The water-soluble reactive dye preferably comprises 3, 4 or 5, morepreferably 3 or 4, especially 3 chromophoric groups linked to apolyamine. The chromophoric groups can be different from each other, butthey are preferably identical to each other.

The polyamine to which the chromophoric groups are linked preferablyconsists of at least three amino groups, more preferably three to six,especially three or four amino groups, joined together by optionallysubstituted aliphatic groups. The amino groups are preferably attachedto one or two --CH₂ -- groups (as illustrated in --HN--CH₂ -- and --CH₂--N(-)--CH₂ --). Preferred polyamines are linear polyamines, for exampleof the formula (I), or branched polyamines, for example of formula (II)wherein each R¹ independently is H or optionally substituted alkyl, nhas a value of 2 to 10, preferably 2 to 6, more preferably 2, and p hasa value of 2 to 6, more preferably 2 or 3: ##STR2##

Reactivity of the dyes is preferably provided by means of a reactivetriazine group linking the chromophoric groups to amino groups in thepolyamine. The reactive triazine group is preferably an s-triazine grouphaving a labile atom or group at the 2-,4- or 6-position, for example agroup of the formula: ##STR3## wherein Y is a labile atom or group.

In light of the above preference for amino groups being attached to--CH₂ -- groups and the chromophoric groups being linked to the nitrogenatoms by means of reactive triazine groups it is preferred for thewater-soluble reactive dyes to contain at least 3, more preferably 3,4or 5, especially 3 or 4, more especially 3 groups of the formula (III):##STR4## wherein: m is from 1 to 6;

Q is H or optionally substituted alkyl or alkylene;

Y is a labile atom or group; and

D is a chromophoric group.

Preferably m is 2, 3 or 4, more preferably 2 or 3, especially 2.

O is preferably H, C₁₋₄ -alkyl or C₂₋₄ -alkylene, more preferably H,methyl or --CH₂ CH₂ --, especially H or --CH₂ CH₂ --.

As will be understood, when Q is H or optionally substituted alkyl thechromophoric group D is a chain terminating chromophoric group and whenQ is optionally substituted alkylene then D is a pendent chromophoricgroup. Thus a dye comprising three chromophoric groups linked todiethylene triamine would have two terminating chromophoric groups andone pendent chromophoric group. When the polyamine istris(2-aminoethyl)amine the corresponding dye would have threeterminating chromophoric groups and zero pendent chromophoric groups.

One preferred class of dye, which presents one aspect of the invention,is of the formula N(Z)₃ wherein each Z independently is of the formula(III) defined above, with the proviso that Q is H or optionallysubstituted alkyl, preferably H or C₁₋₄ -alkyl, especially H.

A second preferred class of dye which may be used in the process is ofthe formula (IV): ##STR5## wherein t is 2, 3 or 4;

r is 3, 4 or5.

q is (t+3)-r; and

Y, R¹, m and D are as hereinbefore defined.

Dyes of formula (III) wherein at least one D is a chromophore other thanan azo chromophore form a further feature of the invention.

R¹ is preferably H or C₁₋₄ -alkyl, more preferably H.

By a labile atom or group it is meant an atom or group which is bound bya chemical bond to the triazine nucleus, which atom or group isdisplaceable by a hydroxyl group of cellulose under mildly alkalineaqueous conditions to form a covalent bond between the triazine nucleusand cellulose. As examples of such atoms or groups there may bementioned halogen atoms, for example F and Cl; sulphonic acid groups;thiocyano groups; quaternary ammonium groups, for exampletrialkylammonium groups and optionally substituted pyridinium groups,for example 3- and 4- carboxy pyridinium groups.

When R¹, Q or an aliphatic group is substituted the substituent ispreferably selected from hydroxy, amino, halo, carboxy and sulpho.

In a preferred embodiment dyes of the invention are tree from --SO₂CH═CH₂ groups and groups which are convertible on treatment with aqueousalkali to --SO₂ CH═CH₂ groups (e.g --SO₂ CH₂ CH₂ OSO₃ H, --SO₂ CH₂ CH₂SSO₃ H, --SO₂ CH₂ CH₂ OPO₃ H and --SO₂ CH₂ CH₂ Cl). Preferably the onlyreactive groups in dyes of the invention are reactive triazine groups.

The chromophoric groups preferably each independently comprise an azo,anthraquinone, phthalocyanine, triphenodioxazine or formazan group.

Preferred azo groups are monoazo and disazo groups. Preferred monoazogroups are formula L--N═N--L¹ --NR¹ -- wherein L is an aryl orheteroaryl group, L¹ is an arylene group and R¹ is as hereinbeforedefined.

It is preferred that each aryl or arylene group independently is a mono-or di-cyclic aryl or arylene group. Preferred aryl groups are optionallysubstituted phenyl and optionally substituted naphthyl, and preferredarylene groups are optionally substituted phenylene and optionallysubstituted naphthylene. Preferred heteroaryl groups are pyridonyl andpyrazolonyl.

A first preferred monoazo group is of the Formula (2) or salt thereof:##STR6## wherein: X is H or sulpho, and

L and R¹ are as hereinbefore defined.

L is preferably optionally substituted phenyl or naphthyl, especially aphenyl or naphthyl group having at least one sulpho substituent. Furtheroptional substituents which may be present on L include a halogen atom,especially chlorine; an alkyl radical, especially C₁₋₄ -alkyl, moreespecially methyl; an acylamino radical, especially acetylamino,benzamido or sulphonated benzamido; amino; hydroxy; and an alkoxyradical, especially C₁₋₄ -alkoxy, more especially methoxy.

As examples of phenyl groups having at least one sulpho substituentthere may be mentioned 2-, 3- or 4-sulphophenyl; 2-sulpho-4-nitrophenyl;2-sulpho-5-nitrophenyl; 4-sulpho2-methylphenyl; 5-sulpho-2-methylphenyl;2-sulpho-4-methylphenyl; 5-sulpho-2-methoxyphenyl;2-sulpho-4-methoxyphenyl; 4-sulpho-2-chlorophenyl;5-acetamido-2-sulphophenyl; 5-sulpho-2-carboxyphenyl:2,4-disulphophenyl; 2,5-disulphophenyl; and 3,5-disulphophenyl.

As examples of naphthyl groups having at least one sulpho substituentthere may be mentioned 1 -sulphonaphth-2-yl; 1,5-disulphonaphth-2-yl;1,5,7-trisulphonaphth-2-yl; 3,6,8-trisuiphonaphth-2-yl;5,7-disulphonaphth-2-yl; 6-sulphonaphth-2-yl; 4-, 5-, 6, or7-sulphonaphth-1-yl: 4,8-disulphonaphth-1-yl, 3,8-disulphonaphth-1-yl;2,5,7-trisulphonaphth-1-yl; and 3,5,7-trisulphonaphth-1 -yl.

Preferred optional substituents which may be present on L¹ are thosementioned above for L.

In groups of Formula (2), --NR¹ -- is preferably at the 6-, 7- or8-position, especially the 6- or 8- position. When --NR¹ -- is at the8-position, it is preferred that X is a sulpho group at the 5- or 6-position.

A second preferred monoazo group is of the Formula (3) or a saltthereof: ##STR7## wherein R³ is H or C₁₋₄ -alkyl;

R² is H, C₁₋₄ -alkyl, C₁₋₄ -alkanoyl or optionally substituted benzoyl,especially benzoyl or sulphobenzoyl, acetyl, propanoyl, n-butanoyl oriso-butanoyl; and

X and R¹ are as hereinbefore defined.

A third preferred monoazo group is of the Formula (4) or salt thereof:##STR8## wherein: pH is an optionally substituted phenyl group,especially sulphophenyl;

R⁴ is CN, CH₃ or carboxy, and

R¹ and X are as hereinbefore defined.

A preferred disazo group is of Formula (5) or salt thereof:

    L--N═N--A--N═N--B--NR.sup.1 --                     (5)

wherein:

A and B are each independently optionally substituted phenylene ornaphthylene: and

R¹ and L are as hereinbefore defined.

It is preferred that B is optionally substituted naphthylene and A isoptionally substituted phenylene. The optional substituents which may bepresent on A or B are preferably independently selected from halo,especially chloro: alkoxy, especially C₁₋₄ -alkoxy; alkyl, especiallymethyl; sulpho; carboxy; hydroxy; amino; acylamino especially asacetamido, benzamido and sulphonated benzamido, and pyrimidinylamino ortriazinylamino cellulose-reactive groups.

As Examples of groups represented by A and B there may be mentionedphenylene, 2-methyl-1,4-phenylene, sulphophenylene, ureidophenylene,7-sulpho-1, 4-naphthylene, 6-sulpho-1,4-naphthylene;8-sulpho-1,4-naphthylene and 6-hydroxy-4-sulpho-1,5-naphthylene.

A preferred anthraquinone group is of the Formula (6) or a salt thereof:##STR9## wherein the anthraquinone nucleus optionally contains asulphonic acid group in the 5-, 6-, 7-, or 8-position; V is a divalentorganic linking group, preferably of the benzene series; and R¹ is ashereinbefore defined.

V is preferably phenylene, diphenylene, or 4,4'-divalent stilbene orazobenzene radicals which are optionally sulphonated. It is preferredthat V contains one sulphonic acid group for each benzene ring presenttherein.

A preferred phthalocyanine group is of the Formula (7) or a saltthereof: ##STR10## wherein Pc is a metallo-phthalocyanine nucleus,preferably copper or nickel phthalocyanine; each R¹ is as hereinbeforedefined; each W independently is a hydroxy or a substituted orunsubstituted amino group, V¹ is a divalent organic linking group,preferably a C₁₋₄ -alkylene or phenylene linking group; and a and b areeach independently 1, 2 or 3 provided that a+b is not greater than 4.

A preferred triphenodioxazine group is of the Formula (8) or a saltthereof: ##STR11## wherein each Y¹ independently is a covalent bond,C₂₋₄ -alkylene, phenylene or sulphophenylene;

U is H or SO₃ H;

W¹ is an optionally substituted triazine group;

T¹ and T² are halo, especially chloro, C₁₋₄ -alkyl, or C₁₋₄ -alkoxy; andeach

R¹ independently is as hereinbefore defined.

Each Y¹ is preferably --C₂ H₄ -- or --C₃ H₆ --, U is preferably SO₃ H,and

T¹ and T² are preferably Cl, methyl or ethyl.

W¹ is preferably a triazine group having one or two a labile atoms orgroups.

A preferred formazan group is of the Formula (9) or a salt thereof:##STR12## wherein: X¹ is H, SO₃ H or Cl;

each p independently has a value of 0, 1 or 2; and

R¹ is as hereinbefore defined;

provided that the formazan group has at least one, and preferably atleast two, sulpho groups.

It is preferred that each p has a value of 1.

Dyes according to the invention may be prepared by a process comprisingcondensation of one or more reactive dyes having at least two reactivegroups with a polyamine, preferably in a liquid medium. It is preferredthat the condensation is performed at 10° C. to 70° C., especially 20 to50° C. more especially 20 to 40° C. The liquid medium is preferably anaqueous medium, especially water. The condensation is preferablyperformed at a pH in the range 5.5 to 11, preferably 5.5 to 9.5, morepreferably 6 to 9. especially 7.5 to 8.5. It is preferred to use anexcess of the reactive dye, for example 3 to 5 moles of the reactive dyeper mole of polyamine when the polyamine is tris(aminoalkyl)amine, morepreferably 2.5 to 3.5, especially about 3.

Examples of suitable polyamines which can be used in the process includetris(2-aminoethyl)amine, diethylene triamine, dipropylene triamine,triethylene tetramine, mono-N-(2-aminoethyl) dipropylene triamine,N,N'-bis(3-aminopropyl)butylenediamine, mono-N-(2-hydroxyethyl)triethylene tetramine, tetraethylene pentamine and pentaethylenehexamine. Preferably the polyamine has a molecular weight below 599.

Although dye formulae have been shown in the form of their free acid inthis specification, the invention also includes dyes and processes usingdyes in the salt form, particularly their salts with alkali metals suchas the potassium, sodium, lithium or mixed sodium/lithium salt.

The process for coloration is preferably performed at a pH of 7 1 to 13,more preferably 10 to 12. pH levels above 7 can be achieved byperforming the process for coloration in the presence of an acid-bindingagent.

The substrate is preferably a natural and artificial textile materialscontaining amino or hydroxyl groups, for example textile material suchas wool, silk, polyamides and modified polyacrylonitrile fibres, andmore preferably a cellulosic textile material, especially cotton. Forthis purpose the dyes can be applied to the textile materials at a pHabove 7 by, for example, exhaust dyeing, padding or printing. Textilematerials are coloured bright shades and possess good fastness to lightand to wet treatments such as washing.

The new dyes are particularly valuable for colouring cellulosic textilematerials. For this purpose the dyes are preferably applied to thecellulosic textile material at a pH above 7 in conjunction with atreatment with an acid-binding agent.

Preferred acid-binding agents include alkali metal carbonates,bicarbonates, hydroxides, metasilicates and mixtures thereof, forexample sodium bicarbonate, sodium carbonate, sodium metasilicates,sodium hydroxide and the corresponding potassium salts. The dyes benefitfrom excellent build-up and high fixation.

The new dyes can be applied to textile materials containing aminegroups, such as wool and polyamide textile materials, from a mildlyalkaline dyebath. The dyeing process can be carried out at a constant orsubstantially constant pH, that is to say the pH of the dyebath remainsconstant or substantially constant during the dyeing process, or ifdesired the pH of the dyebath can be altered at any stage of the dyeingprocess.

The dyes may be in liquid or solid form, for example in granular orpowdered form.

The invention is illustrated but not limited by the following Examplesin which all parts and percentages are by weight unless statedotherwise.

EXAMPLE 1

Preparation of ##STR13## Stage a)

1-hydroxy-2-(1,5-disulphonaphth-2-ylazo)-6-[N-(4,6-dichloro-s-triazin-2-yl)methylamino]-naphthalene-3-sulphonicacid was prepared by coupling diazotised2-aminonaphthalene-1,5-disulphonic acid ontoN-acetyl-2-methylamino-5-hydroxynaphthalene-7-sulphonic acid, removingthe acetyl group by heating to 80° C. in 2N sodium hydroxide solutionand reacting the resultant dyebase with cyanuric chloride at 0-5° C.

Stage b)

Tris(β-aminoethyl)amine (1.246 g) was added to a stirred solution of theproduct from stage a) (36 g. MI 1221) in water (250 ml). The mixture wasstirred at 50° C., pH 8.5, for 2 hours, cooled and methylated spiritswas added slowly with stirring. The precipitated dye was collected anddried to give the title product (23 g. MI 2914) having a λmax at 484 nm.

Stage c)--Dyeing

The title product was applied to cotton by exhaust dyeing in aqueoussoda ash and was found to have good build-up and high fixationefficiency.

EXAMPLE 2

Preparation of ##STR14## Stage a)

2-1-sulphonaphthyl-2-azo)-8-(4,6-dichloro-s-triazin-2-ylamino)-1-hydroxynaphthalene-3,6-disulphonic acid was prepared by condensing cyanuricchloride with1-hydroxy-2-(1-sulphonaphthyl-2-azo)-8-aminonaphthalene-3,6-disulphonicacid at 0.5° C. and pH6.

Stage b)

Tris(β-aminoethyl)amine (0.684 g, 96% strength) was added to a stirredsolution of the product from stage a), (0.0148 m) in water (250 ml). Themixture was stirred at 50° C. and pH 8.5 to 5 hours. A further portionof the product from stage a) (0.0029 mol) was added and the mixture wasstirred for a further 2 hours at 50° C. The mixture was allowed to coolto room temperature, salt solution (8% w/v) was added with stirring andthe resultant precipitate collected and dried to give the title product(11.0 g, 76% strength) having a λmax at 518 nm and εmax of 102.166.

Stage c)--Dyeing

The title product was applied to cotton by exhaust dyeing in presence ofsalt and soda ash and was found to have good build-up and fixation.

EXAMPLE 3

Preparation of ##STR15## Stage a)

1-hydroxy-2-(2-sulpho-4-methyl phenylazo)-8-(4,6dichloro-s-triazin-2-ylamino)naphthalene-3,6-disulphonic acidwas prepared by coupling diazotised 2-amino-5-methylbenzene sulphonicacid onto 1-hydroxy-8-(dichloro-s-triazinylamino)naphthalene-3,6-disulphonic acid.

Stage b)

Tris(βaminoethyl)amine (1.01 g) was added to a solution of the productfrom stage a) (43 g, MI 1599) in water (300 ml). The mixture was stirredat 50° C. and pH 8.5 for 2 hours then allowed to cool to roomtemperature. Methylated spirits was added slowly with stirring and theresultant precipitate collected and dried to give the title product (30g) having a λmax at 516 nm.

Stage c)--Dyeing

The title product was applied to cotton by exhaust dyeing in thepresence of salt and soda ash and was found to have good fixationefficiency.

EXAMPLE 4

Stage a)

The method of Example 2 was repeated except that in place istris-(β-aminoethyl)amine there was used an equimolar amount ofdiethylene thiamine. The resultant product had a λmax at 518 nm.

Stage b)--Dyeing

The product from stage a) was applied to cotton at 90° C. in thepresence of salt and soda ash and was found to have good build-up andfixation efficiency.

EXAMPLE 5

The method of Example 3 was repeated except that in place istris-(β-aminoethyl)amine there was used an equimolar amount ofdiethylene triamine. The resultant product had a λmax at 516 nm.

Stage b)--Dyeing

The product from stage a) was applied to cotton in presence of salt andsoda ash and was found to have good build up.

EXAMPLE 6 ##STR16## Stage a)

A solution of1-hydroxy-6-[N-methyl-N-(dichloro-s-triazinyl)]-amino-2-[3-methyl-4-(2,5-disulphophenylazo)phenyl azo] naphthalene-3-sulphonic acid (0.0248 mmol) andtris(β-aminoethylyamine (0.0083 mmol) was stirred at pH 8.5 and 45-50°for 6 hours. On cooling, potassium chloride solution (7.5% w/v) wasadded and the precipitate was collected and dried to give the titleproduct having a λmax at 522 nm, εmax 128.000.

Stage b)

The product from stage a) was applied to cotton in presence of soda ashand NaCl and was found to have good fixation and build-up.

EXAMPLE 7

Preparation of a reactive dye of the formula (10) ##STR17## wherein p is2 and D is a 1-hydroxy-2-(2'-sulphophenylazo)-3,6-disulphonaphthyl-8-amino group.

Stage a)

Diethylene triamine (8.7 mmol) was added to a solution of8-dichloro-s-triazinylamino-1-hydroxy-2(2'-sulphophenylazo)naphthalene-3,6-disulphonicacid (27.3 mmol) in water (200 ml). The mixture was stirred at 50° C.and pH 8.5 for 8 hours. On cooling the solution was added to methylatedspirits (1 litre) and the precipitated solid was collected and dried togive the title product (7.8 mmol) having a λmax at 506 nm.

Stage b)--Dyeing

The title product was applied to cotton by exhaust dyeing in presence ofNaCl and soda ash.

EXAMPLE 8

Preparation of a dye of formula (10) wherein p is 2 and D is of theformula: ##STR18## Stage a)

1-(4sulphophenyl)-3-carboxy-4-(2-sulpho-4-dichloro-s-triazinylamino-phenylazo)pyrazol-5-one was prepared by condensation of1-(4-sulphophenyl)-3-carboxy-4-(4-amino-2-sulphophenyl azo)pyrazol-5-one with cyanuric chloride at pH 6.5.

Stage b)

Diethylene triamine (8.3 mmol) was added to a solution of the productfrom stage a) (26.3 mmol) in water (200 ml). After stirring for 4 hoursat 50° C. and pH 8.5 the mixture was added, with stirring, to methylatedspirits. The precipitate was filtered-off and dried to give the titleproduct (4.5 mmol) having a λmax at 449 nm.

Stage c)--Dyeing

The title product was applied to cotton by exhaust dyeing in presence ofsalt an soda ash and was found to have good build up and fixation.

EXAMPLE 9

Preparation of a dye of formula (10) wherein p is 2 and D is of theformula: ##STR19## Stage a)

N-(dichloro-s-triazinyl)-3-ureido-4(3,6,8-trisulpho naphthyl-2-azo)aniline was prepared by condensation, at 0° to 5° and pH 6.5, ofcyanuric chloride with 3-ureido-4-(3,6,8-trisulphonaphthyl-2-azo)aniline.

Stage b)

Diethylenetriamine (5.4 mmol) was added to a solution of the productfrom stage a) (16.2 mmol in water (200 ml). The mixture was stirred at50° C. and pH 8.5 for 15 hours. After cooling to room temperature themixture was added to methylated spirits (740p, 1 litre) and theprecipitated solid collected and dried to give the title product (4mmol) having a λmax at 431 nm.

Stage c)

The title product was applied to cotton by exhaust dyeing in presence ofsoda ash and NaCl and was found to have good fixation.

EXAMPLE 10

Stage a)

The method of Example 3, stage b), was followed except that in place ofthe product from step a) there was used1-hydroxy-2-(2'-sulpho-5'-acetylaminophenylazo)-8-(4,6-dichloro-s-triazin2-ylamino)naphthalene-3,6-disulphonic acid. The resultant reactive dye had a λmaxat 505 nm.

Stage b)--Dyeing

The title product was applied to cotton by exhaust dyeing in presence ofNaCl and soda ash and was found to have good fixation.

EXAMPLE 11

Preparation of a dye of Formula (10) wherein p is 2 and D is of theformula: ##STR20##

The method of Example 7 was repeated except that in place of8-dichloro-s-triazinylamino-1-hydroxy2(2'-sulphophenylazo)naphthalene-3,6-disulphonic acid there was used1-hydroxy-2-(phenylazo)-8-(4,6-dichloro-s-triazine-2-ylamino)naphthalene-3,6-disulphonicacid.

The resultant dye had a λmax at 509 nm and was found to have goodbuild-up and fixation when applied to cotton by exhaust dyeing.

EXAMPLE 12

Preparation of a dye of Formula (10) wherein p is 2 and D is of theformula: ##STR21##

The method of Example 7 was repeated except that in place of8-dichloro-s-triazinylamino-1-hydroxy2(2'-sulphophenylazo)naphthalene-3,6-disulphonic acid there was used6-(N-dichloro-s-triazinylmethylamino)-1-hydroxy-2-(1,5-disulphonaphthyl-2-azo)naphthalene-3-sulphonicacid.

The resultant dye had a λmax at 484 nm and was found to have goodbuild-up and fixation when applied to cotton by exhaust dyeing.

EXAMPLE 13

The method of Example 2 was repeated except that in place of tris(β-aminoethyl)amino there was used an equivalent amount of an amine ofthe formula H₂ N--(CH₂)₆ --NH--(CH₂)₆ --NH₂.

The resultant dye had a λmax at 516 nm and was found to have goodbuild-up and fixation when applied to cotton by exhaust dyeing.

EXAMPLE 14

Preparation of a Reactive Dye of the Formula (10) Wherein p is 6 and Dis a 1-Hydroxy-2'-(2-Sulphophenylazo)-3,6-Disulphonaphthyl-8-Amino Group

The method of Example 7 was repeated except that in place of diethylenetriamine there was used an equivalent amount of an amine of the formulaH₂ N(CH₂)₆ NH(CH₂)₆ NH₂.

The resultant dye had a λmax at 516 nm and was found to have goodbuild-up and fixation when applied to cotton by exhaust dyeing.

EXAMPLE 15

Preparation of a dye of the formula (11): ##STR22## wherein x+y+z isfrom 5 to 6 and Q is of the formula (12): ##STR23##

A solution of 8-dichloro-s-triazinylamino-1-hydroxy-2-(1-sulphonaphth-2-ylazo) naphthalene-3,6-disulphonicacid (MI 1705, 33 g) was mixed with Jeffamine™ T403 (from TexacoCorporation) (MI 440, 0.0059 m) and the solution stirred at pH 8.5 and60° C. for 15 hours. After allowing to cool, salt (20% w/v) was added tothe stirred solution, the precipitated solid was collected, desalinated(visking tubing) and reprecipitated with methylated spirits to give thetitle product (11.0 g, Ml 3000) λmax 523 nm, εmax 106000.

EXAMPLE 16 ##STR24##

A solution of1-hydroxy-2-(2-sulpho-4-methoxyphenylazo)-7-N-(4,6-dichloro-s-triazinyl)methylaminonaphthalene-3-sulphonic acid (0.033 moles) was dissolved inwater at pH7. Tris (β-aminoethyl)amine (1.46 g, 0.01 moles) was added tothe solution and the mixture was stirred at 50° C. and pH 10 for 3hours. The mixture was allowed to cool and screened to remove anyinsoluble material. Salt (15% w/v) was added and the resultingprecipitate was collected and dried to give the title product as itssodium salt (14.3 g, MI 2000), having λmax at 502 nm.

EXAMPLE 17

Preparation of ##STR25## Stage (a)

Cyanuric chloride (6 g) dissolved In acetone was added to ice/water withvigorous stirring followed by 2,4-diaminobenzene sulphonic acid. Themixture was stirred at 0° C. and pH3 for 1.5 hours, screened and the pHadjusted to 2.0. 2N sodium nitrite solution (16.5 ml, 0.033 moles) wasadded at 0° C. and pH2. After 2 hours,1-hydroxy-7-aminonaphthalene-3-sulphonic acid (0.03 moles) was added;the mixture was stirred for 6 hours at 0° C. and pH2 to give a solutionof8-(2-sulpho-5-[dichloro-s-triazinylamino]phenylazo)-7-amino-1-hydroxynaphthalene3-sulphonicacid.

Stage b

Tris (β-aminoethyl) amine (1.31 g) was added to the product of stage a)and the mixture was stirred at 50° C. and pH 9.5 for 4 hours. Aftercooling to 20° C. the mixture was screened and salt (20% w/v) was addedto the stirred filtrate. The sodium salt of the precipitated titleproduct was collected and dried.

EXAMPLE 18 ##STR26##

Example 17 was repeated except that in place of the tris(β-aminoethyl)amine there was used diethylene triamine.

The title dye was obtained in a yield of 8.6 g, λmax 536 mn.

The title dye may be applied to cotton by exhaust dyeing under alkalineconditions.

EXAMPLE 19 ##STR27##

A solution of1-amino-4-(3'-dichloro-s-triazinylamino-4'-sulphophenylamino)anthraquinone-2-sulphonic acid (0.03 moles) was dissolved in water. Tris(β-aminoethyl) amine (1.31 g, 0.009 moles) was added and the mixture washeated to 50° C. and stirred at pH 9.5 for 5 hours. The pH was loweredto 6.5 and the mixture allowed to cool to room temperature. Salt (20%w/v) was added with stirring and the resultant precipitate was collectedand dried to give the title product as its sodium salt (12.5 g). Thetitle dye had a λmax at 580 mn.

I claim:
 1. A process for the coloration of a substrate comprisingapplying thereto at a pH above 7 a water-soluble reactive dye of theformula N(Z)₃, wherein each Z is independently a group of the formula(III): ##STR28## wherein: m is from 1 to 6;Q is H or optionallysubstituted alkyl; Y is a labile atom or group; and D is a chromophoricgroup of the formula

    L--N═N--L.sup.1 --NR.sup.1 --

wherein L is an aryl or heteroaryl group, L¹ is an arylene group and R¹is H or C₁₋₄ alkyl.
 2. A process according to claim 1, wherein D is achromophoric group of the formula: ##STR29## wherein X is H or a sulphogroup and L and R¹ are as defined in claim
 1. 3. The process accordingto claim 1, wherein D is a chromophoric group of the formula: ##STR30##4. The process according to claim 1, wherein the water-soluble reactivedye is applied to the substrate at a pH above 7 by exhaust dyeing,padding or printing.
 5. A water-soluble reactive dye of the formulaN(Z)₃, wherein each Z independently is of the formula (III): wherein:mis from 1 to 6; Q is H or optionally substituted alkyl Y is a labileatom or group; and D is a chromophoric group of the formula:

    L--N═N--L.sup.1 --NR.sup.1 --

wherein L is an aryl or heteroaryl group, L¹ is an arylene group and R¹is H or C₁₋₄ alkyl.
 6. The water soluble reactive dye according to claim5, wherein D is a chromophoric group of the formula: ##STR31## wherein Xis H or a sulpho group and L and R¹ are as defined in claim
 5. 7. Thewater-soluble reactive dye according to claim 5, wherein thewater-soluble reactive dye of the formula N(Z)₃ is selected from thegroup consisting of dyes of the formula: ##STR32##
 8. The water-solublereactive dye according to claim 5, wherein D is a chromophoric group ofthe formula